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  • Published Article: Effects of Oxygen Modification on the Structural and Magnetic Properties of Highly Epitaxial La0.7Sr0.3MnO3 (LSMO) thin films
Title: Effects of Oxygen Modification on the Structural and Magnetic Properties of Highly Epitaxial La0.7Sr0.3MnO3 (LSMO) thin films
Abstract

La0.7Sr0.3MnO3, a strong semi-metallic ferromagnet having robust spin polarization and magnetic transition temperature (TC) well above 300 K, has attracted significant attention as a possible candidate for a wide range of memory, spintronic, and multifunctional devices. Since varying the oxygen partial pressure during growth is likely to change the structural and other physical functionalities of La0.7Sr0.3MnO3(LSMO) films, here we report detailed investigations on structure, along with magnetic behavior of LSMO films with same thickness (~30 nm) but synthesized at various oxygen partial pressures: 10, 30, 50, 100, 150, 200 and 250 mTorr. The observation of only (00 l) reflections without any secondary peaks in the XRD patterns confirms the high-quality synthesis of the above-mentioned films. Surface morphology of the films reveals that these films are very smooth with low roughness, the thin films synthesized at 150 mTorr having the lowest average roughness. The increasing of magneticTCand sharpness of the magnetic phase transitions with increasing oxygen growth pressure suggests that by decreasing the oxygen growth pressure leads to oxygen deficiencies in grown films which induce oxygen inhomogeneity. Thin films grown at 150 mTorr exhibits the highest magnetization withTC = 340 K as these thin films possess the lowest roughness and might exhibit lowest oxygen vacancies and more » defects. Interpretation and significance of these results in the 30 nm LSMO thin films prepared at different oxygen growth pressures are also presented, along with the existence and growth pressure dependence of negative remanent magnetization (NRM) of the above-mentioned thin films.

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Authors:
; ; ; ; ; ; ; ;
Publication Date:
NSF-PAR ID:
10154004
Journal Name:
Scientific Reports
Volume:
10
Issue:
1
ISSN:
2045-2322
Publisher:
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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